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41.
42.
  1. As a highly endangered species, the giant panda (panda) has attracted significant attention in the past decades. Considerable efforts have been put on panda conservation and reproduction, offering the promising outcome of maintaining the population size of pandas. To evaluate the effectiveness of conservation and management strategies, recognizing individual pandas is critical. However, it remains a challenging task because the existing methods, such as traditional tracking method, discrimination method based on footprint identification, and molecular biology method, are invasive, inaccurate, expensive, or challenging to perform. The advances of imaging technologies have led to the wide applications of digital images and videos in panda conservation and management, which makes it possible for individual panda recognition in a noninvasive manner by using image‐based panda face recognition method.
  2. In recent years, deep learning has achieved great success in the field of computer vision and pattern recognition. For panda face recognition, a fully automatic deep learning algorithm which consists of a sequence of deep neural networks (DNNs) used for panda face detection, segmentation, alignment, and identity prediction is developed in this study. To develop and evaluate the algorithm, the largest panda image dataset containing 6,441 images from 218 different pandas, which is 39.78% of captive pandas in the world, is established.
  3. The algorithm achieved 96.27% accuracy in panda recognition and 100% accuracy in detection.
  4. This study shows that panda faces can be used for panda recognition. It enables the use of the cameras installed in their habitat for monitoring their population and behavior. This noninvasive approach is much more cost‐effective than the approaches used in the previous panda surveys.
  相似文献   
43.
For the estimation of population mean in simple random sampling, an efficient regression-type estimator is proposed which is more efficient than the conventional regression estimator and hence than mean per unit estimator, ratio and product estimators and many other estimators proposed by various authors. Some numerical examples are included for illustration.  相似文献   
44.
A selective procedure using synthetic substrates for determination of exo-1,4,-beta-glucanases in a mixture of exoglucanases , endoglucanases , and beta-glucosidases is formulated. The heterobiosides , p- nithrophenyl -beta-D- cellobioside ( pNPC ) or p-nitrophenyl-beta-D-lactoside ( pNPL ), were used as selective substrates for the measurement of exoglucanase activity. The exoglucanases (especially cellobiohydrolases , which split off cellobiose units from the nonreducing end of the cellulose chain) specifically act on the agluconic bond (between p-nitrophenyl and the disaccharide moiety) and not on the holosidic bond (between the two glucose units of cellobiose). The interfering effect of beta-glucosidase, which acts on both agluconic and holosidic bonds, is overcome by the addition of D-glucono-1,5-delta-lactone, a specific inhibitor of beta-glucosidases. The interference of endoglucanases , which also act on both agluconic and holosidic bonds, can be compensated for by prior standardization of the assay procedure with a purified endoglucanase from the studied mixture of cellulases.  相似文献   
45.
The investigation of Encelia canescens afforded, in addition to several known compounds, four new dimeric p-hydroxyacetophenone derivatives, two epimeric chromene dimers and two epimeric mixed dimers of euparin and encecalin. Furthermore, derivatives of tremetone and of encecalin were present. The structures were elucidated hy high field 1H NMR spectroscopy.  相似文献   
46.
Abstract In the field, adult males of the grasshopper Phymateus morbillosus are able to fly for up to 1 min and cover up to c. 100 m, whereas females, although fully winged, are apparently unable to get airborne. Morphometric data indicate that the males are lighter, have longer wings, a higher ratio of flight muscles to body mass, and a lower wing load value than females. It was investigated whether this inability of females to fly is related to fuel storage, flight muscle enzymatic design and/or the presence and quantitative capacity of the endocrine system to mobilize fuels. In both sexes, readily available potential energy substrates are present in the haemolymph in similar concentrations, and the amount of glycogen in flight muscles and fat bodies does not differ significantly between males and females. Mass-specific activities of the enzymes GAPDH (glycolysis), HOAD (fatty acid oxidation) and MDH (citric acid cycle) in flight muscles are significantly lower in females compared with males, and mitochondria are less abundant in the flight muscles of females. There is no significant difference between the ability of the two sexes to oxidize various important substrates. Both sexes contain three adipokinetic peptides in their corpora cardiaca; the amount of each peptide in female grasshoppers is higher than in males.
Thus, despite some differences listed above, both sexes appear to have sufficient substrates and the necessary endocrine complement to engage in flight. It seems more likely, from the morphometric data above, that the chief reason for flightlessness is that P. morbillosus females cannot produce sufficient lift for flight; alternatively, the neuronal functioning associated with the flight muscles may be impaired in females.  相似文献   
47.
Abstract Photoproduction of hydrogen, nitrogenase activity (acetylene reduction) and hydrogenase activity (methylene blue dye reduction) were studied in free and alginate immobilized whole cells of a purple non-sulfur photosynthetic bacterium Rhodobacter sphaeroides O.U. 001. Four-fold increase in hydrogen production, two-fold increase in nitrogenase activity and 1.2-fold increase in the hydrogenase activity were observed in immobilized cells compared to free cells. Effect of various inhibitors (CO and C2H2) and electron donor (H2) on the above three functions by free and immobilized cells has also been studied.  相似文献   
48.
Parkin mutations produce Parkinson’s disease (PD) in humans and nigrostriatal dopamine lesions related to increased free radicals in mice. We examined the effects of NP7, a synthetic, marine derived, free radical scavenger which enters the brain, on H2O2 toxicity in cultured neurons and glia from wild-type (WT) and parkin null mice (PK-KO).NP7, 5-10 μM, prevented the H2O2 induced apoptosis and necrosis of midbrain neuronal and glial cultures from WT and PK-KO mice. NP7 suppressed microglial activation and the H2O2 induced drop-out of dopamine neurons. Furthermore, NP7 prevented the increased phosphorylation of ERK and AKT induced by H2O2. NP7 may be a promising neuroprotector against oxidative stress in PD.  相似文献   
49.
Maritime Spatial Planning (MSP) needs to incorporate spatial information on human impacts. As human activities and uses increase in marine and coastal waters around the world, pressures in ecosystems are also increasing, leading to multiple adverse effects on different species and habitats. The European Directive on MSP aims to achieve an integrated approach to marine governance, whilst securing and maintaining the healthy status of marine and coastal waters, in accordance with the Marine Strategy Framework Directive. The latter requires Member States to develop assessments not only on pressures and impacts, but also on the state of the marine environment and then take measures towards reaching a Good Environmental Status by 2020.The Portuguese Maritime Spatial Plan – Plano de Ordenamento do Espaço Marítimo (POEM) was developed between 2009 and 2012. In 2014 a law establishing the Basis for the Spatial Planning and Management of the National Maritime Space was enacted and in 2015 the framework for the elaboration of a new national Maritime Spatial Plan, named Situation Plan, was established. Portugal will face, in the next five years, the challenge of planning and managing its marine space, whilst promoting its sustainable use and protection.This study adapted a cumulative effects assessment model to understand how the impacts from multiple threats affect the marine and coastal ecosystems and, how this information can be used to improve the management process. Information was gathered on intensity and distribution of activities and uses for the Portuguese continental subdivision marine area, quantified and mapped their cumulative impacts in marine ecosystems, and overlapped with the POEM. Results show that impacts are spreading from the coast up to the Contiguous Zone. Higher scores appear in Transitional and Coastal Waters in the north (Viana do Castelo/Figueira da Foz), centre (Peniche/Setúbal) and south (Lagos/Faro). In some areas with higher ranks, statutes of nature conservation are already in place, but potential activities may still occur on top of existing ones. This study shows that the adapted model is a helpful tool to clarify ocean planning, identify areas of potential conflicts among users and support the decision making process.  相似文献   
50.
Focal contacts of spreading platelets with the substratum   总被引:1,自引:0,他引:1  
Contacts with glass substratum formed by the spreading rabbit platelets were examined by an antibody-exclusion method; monoclonal antibodies against 80 kD bovine serum protein were used. It was found that platelets form focal contacts in the course of spreading. The size of the largest focal contacts formed by platelets is smaller than that of the contacts formed by fibroblasts. The antibody-exclusion method revealed focal contacts of platelets much more clearly than interference reflection microscopy (IRM). The similarity of reactions involved in spreading platelets and of large nucleus-containing tissue cells is discussed.  相似文献   
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